Cells That Are Infected, Damaged, or Have Reached the End

Multiple Choice

Cells that are infected, damaged, or have reached the end of their functional life span often undergo "programmed cell death." This controlled cell suicide is called apoptosis. Select the appropriate description of this event on a cell's life cycle.

A) Apoptosis is regulated by cell surface receptors that signal when a cell has reached its density-dependent limits.
B) During apoptosis, dying cells leak out their contents, including digestive enzymes that also destroy healthy cells.
C) During apoptosis, cellular agents chop up the DNA and fragment the organelles and other cytoplasmic components of a cell.
D) Each cell organelle has protein signals that initiate the breakdown of the organelle's components, which leads to cell death.